My first weather related thread in quite some time, so hopefully it comes as a respite from the usual theme of thread.
OK, so this thread is more pertinent to those in the UK of a potential cold spell arriving over the next 5-8 days. When I say potential, I mean
potential for disruption.
Now before I go any further, let me mitigate the usual responses to threads like this from those of you who cannot see the bigger picture…
YES, WE ALL KNOW WINTER BRINGS COLD AND SNOW but that Is not why I post these threads, I do it because contrary to belief, there is a large population
in the UK who live rurally and conduct their lives rurally who are more likely to be impacted by bad winter weather, notably Ice and Snow. Not to
mention the bias from the general media weather service towards London and other centers of population – and at times the general vagueness of the
reports, with occasionally little lead time.
Now that that’s out of the way, let’s discuss it…
The weather patterns over the previous few days and the projected patterns over the next few days are complicated to say the least. A lot of problems
at that the models are struggling to grasp is what impact the Canadian/Alaskan setup will have on the UK, believe it or not, there is a link.
One of the leading indicators is the position of the Polar Vortex. This moves and can split. As a general rule, we don’t want to see the PV over
The upper air temperature could be at or below -10 for much of the UK during this period, negating any kind or marginality. (Generally if it’s
below -5 to -7, it’ll be the white stuff)
What we can expect to see is a steady increase in Arctic Maritime Air spill down over Scotland on Wednesday, through Wednesday night. The air will be
chilly and with a trough moving towards the colder embedded air from a deep LP. We will start to see the change to snow over the high ground
initially, providing blizzard conditions for the higher routes in Scotland and N England. In northern areas we will see snow down to around 500m to
start off with. As the week progresses we will see that colder air become more established and snow showers rushing in on the brisk wind, occasional
blizzards sweeping from the N as the week draws to a close. The further N or E you are (IMO), the more potential for disruption.
As the new week begins, we will see a respite from the heavier snow but it will remain cold with possible ice days as the wind veers more E’rly, not
ruling out all show as North Sea convection may aid a few further showers off the E, but there are tentative signs that we could lead to a more mobile
milder set up or a re-load of the cold in time for Christmas, such is the nature of forecasting out with a reliable time frame with so many
“unusual” variables. Neither of which I am sure about yet as that really is pushing the boat out.
I will try to keep up with this thread and post further updates if I can.
Please don’t look at the Express or the Mail for your sources as these will definitely tell you The Day After Tomorrow is here!
**Please bear in mind that this is pushing the boundaries of what I normally forecast but given the complexities and potential of what is going on
with the upper atmosphere and the downstream effects closer to home, I feel that it warrants a thread in good time (for potential).